The invention relates to a sanitary insert unit having a jet regulator, having an attachment screen, which is arranged upstream of the jet regulator on the inflow side, and having a throughflow-quantity regulator, which is provided between the jet regulator and attachment screen and has a flow-restricting body which is made of elastic material and encloses, between itself and a regulating profiling provided on a circumferential wall, a control gap which changes under the pressure of the water flowing therethrough, wherein the throughflow-quantity regulator is retained in a releasable manner on the jet regulator and the attachment screen is retained in a releasable manner on the throughflow-quantity regulator.
Applicant's EP 0 733 148 A1 has already disclosed a sanitary insert unit having a jet regulator, having an attachment screen, which is arranged upstream on the inflow side, and having a throughflow-quantity regulator, which is arranged between the jet regulator and attachment screen. While the jet regulator is intended to form a homogenous and non-splashing water jet, the attachment screen is intended to hold back the particles of dirt possibly entrained in the water flowing therethrough. The interposed throughflow-quantity regulator has the task of adjusting, and limiting, to a fixed maximum value, irrespective of the water pressure, the volume of water flowing through per unit of time. For this purpose, the throughflow-quantity regulator has an annular flow-restricting body which is made of elastic material and encloses, between itself and a regulating profiling provided on a circumferential wall, a control gap which changes under the pressure of the water flowing through. The throughflow-quantity regulator, the attachment screen and the jet regulator of the previously known insert unit each have, at their ends which are directed towards one another, matching connectors, which ensure that these installation parts are connected in a releasable manner. This makes it possible for the jet regulator of the previously known insert unit to be used, possibly also at random or accidentally, with the throughflow-quantity regulator alone or with the attachment screen alone. However, if the jet regulator is used with the throughflow-quantity regulator alone, there is, inter alia, a risk of particles of dirt possibly entrained in the water stream passing into the quantity regulator and giving rise there to poor performance, and in particular to a lower output capacity, of the throughflow-quantity regulator. As a result of the installation parts being randomly combined in this way, there is a risk of the previously known insert unit not being able to perform its intended function, or not being able to do so in optimum fashion.